Dzhokhar Tsarnaev, a suspect in the Boston Marathon bombing, is shown in a photo from his Russian social media site account. / none

by Chuck Raasch, Judy Keen and Gregg Zoroya, USA TODAY

by Chuck Raasch, Judy Keen and Gregg Zoroya, USA TODAY

The Tsarnaev brothers - suspects in the bombings at Monday's Boston Marathon - were seen as modest and athletic, the kind of kids that made neighbors feel comfortable.

But conflict was apparently stirring inside the older brother, Tamerlan, who was killed by police in a shootout Friday. He told an interviewer before a Golden Gloves boxing competition in Salt Lake City: "I don't have a single American friend. I don't understand them." He lamented the breakdown of "values," and worried that "people can't control themselves."

Police have identified Tamerlan Tsarnaev, 26, as the Boston bombing suspect killed in a dramatic firefight in Watertown, Mass., just outside Boston. A massive police manhunt for his brother, Dzhokhar, 19, ended Friday night with him in custody in Watertown.

Tamerlan Tsarnaev had a wife and toddler daughter. His mother-in-law said Friday her family is sickened by the horror inflicted by the deadly attack.

Judith Russell, whose daughter Katherine was married to Tamerlan Tsarnaev, read a statement from inside her home in North Kingstown, R.I., through a partially open doorway.

"Our daughter has lost her husband today, the father of her child. We cannot begin to comprehend how this horrible tragedy occurred," Russell said. "In the aftermath of the Patriots' Day horror we know that we never really knew Tamerlan Tsarnaev."

In the interview before the boxing competition, published in 2010 in The Comment, a Boston University College of Communication magazine, Tamerlan Tsarnaev also expressed a dream of boxing for the U.S. Olympic team.

He described himself as a devout Muslim who also liked the raunchy spoof film Borat, in which actor Sasha Baron Cohen plays a sex-obsessed TV reporter from Kazakhstan on a mission to try to understand American culture.

In an online photo layout showing him working out with other athletes, the older Tsarnaev was quoted as saying he was a native of Chechnya who fled the country with his family in the early 1990s and lived in Kazakhstan for several years before coming to the United States in the early 2000s as a refugee. He expressed bitterness toward Russia, which has been locked in a struggle with Chechnyan separatists for many years.

In a series of photos in the article that show him working out with other athletes at a martial arts center in Boston, Tamerlan poses in sweats, wearing blue-and-white boxing gloves. In one photo, he is stripped to the waist, flexing his muscles while sparring. He said he weighed 196 pounds. A caption said he rarely takes his shirt off because "I'm very religious."

He also said that he no longer drinks alcohol or smokes tobacco. "God said no alcohol," he is quoted as saying.

Tsarnaev told Hirn that he had a girlfriend who is of Portuguese and Italian descent and who converted to Islam. "She's beautiful, man," he was quoted as saying. He joked that the white loafers he sometimes wore made him "dressed European-style."

There were posts on social media with accounts allegedly tied to the two brothers that suggested not all may have been as calm as it seemed on the surface. A YouTube account, for instance, under the name of Tamerlan Tsarnaev linked to a speech by Feiz Mohammed, an Australian Muslim cleric who has called for Muslim youth to become holy warriors and who advocated the beheading of a Dutch politician who had compared Islam to Nazism. USA TODAY was unable to independently verify the authenticity of that account.

But the thought that either of the Tsarnaevs could have unleashed the death and destruction that have kept Boston on high alert and moved it toward somber recovery this week seemed foreign to those who knew them.

Peter Manfredo Sr., a boxing coach in Narragansett, R.I., met Tamerlan Tsarnaev when the New England Golden Gloves championship team traveled to the nationals in Salt Lake City in 2009.

"He seemed like a normal guy," Manfredo said. "He was a pretty humble guy" who "took it in stride" when he lost his first fight. "When he lost, he said he'd chalk it up as a learning experience."

Manfredo said he and Tsarnaev went to dinner a couple of times with other coaches and boxers.

Manfredo was surprised when he learned Friday that Tsarnaev was allegedly one of the Boston bombers. "Who knows what goes on in people's minds?" he said.

"Quiet, respectful," was how George McMasters, the director of aquatics at Harvard University, described Dzhokhar Tsarnaev, whom he said he hired as a lifeguard 2½ years ago. Nothing ever came up that raised suspicions in McMasters, an ex-Marine who says he interrogated prisoners in Guantanamo Bay for the National Guard in 2003 and 2004 and helped search for terrorists in Iraq in 2005 and 2006.

"He kept to himself, was on time for work, watched the water, never had problems with other guards he was working with," McMasters, 56, told USA TODAY in a telephone interview from Watertown, Mass., a city locked down as police searched for Dzhokhar Tsarnaev on Friday morning.

"It is surreal for me, considering that I have been dealing with these guys for 10 years," McMasters said, referring to the terror suspects. "And then I come home, and they are in my backyard, in my pool."

As the search and shootout between police and the brothers unfolded, neighbors, employers, friends and others who encountered the two young men who came from a Russian region near Chechnya described the two brothers as the last people they'd suspect of setting off the bombs that killed three people and maimed more than 170 others on Monday near the finish line of the Boston Marathon.

"It is crazy, it is not possible, I can't believe it," Ruslan Tsarni, described as the boys' uncle, told reporters who came to his suburban Maryland neighborhood outside Washington, D.C. "Myself, when I heard this on TV news, I was thinking, 'Who can do this stuff?' It is crazy, it is unbelievable."

"Somebody radicalized them, but it is not my brother," Tsarni told reporters in another exchange later. The Associated Press identified the father as Anzor Tsarnaev and said it contacted him in Russia.

Tsarni called his nephews "losers" and said he had not seen them in more than seven years. He added, "I respect this country, I love this country."

He said the brothers "put a shame on our family" and on ethnic Chechens.

Anzor Tsarnaev spoke with the Associated Press by telephone from the Russian city of Makhachkala on Friday.

"My son is a true angel," the elder Tsarnaev said of his younger son, the subject of an intense manhunt. "Dzhokhar is a second-year medical student in the U.S. He is such an intelligent boy. We expected him to come on holidays here."

The young men were athletic. Tamerlan was a champion boxer. Dzhokhar was a wrestler at the Cambridge Rindge and Latin School in Cambridge, Mass. He was named a Greater Boston League Winter All-Star in 2011.

Both had pursued higher education, Tamerlan as a student for three semesters at Bunker Hill Community College from 2006-2008. Dzhokhar was studying at the University of Massachusetts campus in Dartmouth.

The brothers had been living together on Norfolk Street in Cambridge, Mass. Tsarni, of Montgomery Village, Md., told the Associated Press that the men lived together near Boston and have been in the United States for about a decade.

In 2010, Tamerlan received the prestigious Rocky Marciano Trophy given to the New England heavyweight champ, the Lowell Sun reported.

Larry Aaronson, a retired history teacher at Cambridge Rindge and Latin School, where Dzhokhar graduated in 2011, is the brothers' neighbor and got to know Dzhokhar while taking photos of the high school wrestling team and other school activities.

"It's completely out of his character," Aaronson said of Dzhokhar's alleged role in the bombings. "Everything about him was wonderful. He was completely outgoing, very engaged, he loved the school. He was grateful not to be in Chechnya."

Dzhokhar was not overtly political or religious, Aaronson says. "He spoke and acted like any other high school kid."

Aaronson says he can't reconcile the young man he knows with the characterizations he's seeing in the media. "I cannot do it," he says. "I mean this from the deepest part of my heart: It's not possible it's the same person. It's just not possible."

A former neighbor, Emily Long, told Fox News she saw no signs of radicalization and that the brothers and their parents seemed "so thankful to be in America." She said she lived next door to them a few years ago and still exchanges Christmas cards with them. "My heart breaks for the mom and dad, they've already been through so much," she said.

She said Dzhokhar would often see her arriving from the grocery store and, unsolicited, help her carry in her groceries.

"When I think of him (Dzhokhar) I think of his sweet smile," Long told Fox.

James Auclair was one of the prior tenants of the Norfolk Street apartment in Cambridge before the Tsarnaevs moved in.

He said it was a top-floor, two-bedroom apartment in a neighborhood of mixed ethnicities, mainly Brazilians and Portuguese.

"It was the kind of place where people were coming and going all the time," said Auclair, 50, who lived in the unit from 1996 until about 1999.

In May 2011, as a high school senior, Dzhokhar Tsarnaev was awarded a $2,500 City Scholarship from the city of Cambridge to pursue higher education.

Before moving to the United States, Dzhokhar attended School No. 1 in Makhachkala, the capital of Dagestan, a predominantly Muslim republic in Russia's North Caucasus that has become an epicenter of the Islamist insurgency that spilled over from Chechnya.

His profile on the Russian social-networking site Vkontakte says he lists his languages as English, Russian and Nohchiyn Mott (a Chechen language). His worldview is described as "Islam" and he says his personal goal is "career and money."